Final answer:
The fundamental cause of WW1 was a combination of militarism, alliances, imperialism, and nationalism.
Step-by-step explanation:
The fundamental cause of World War I can be attributed to several factors, with the assassination of Archduke Ferdinand being just one of them. The main causes of the war were militarism, alliances, imperialism, and nationalism.
Militarism refers to the arms race and the belief in the importance of military power. Alliances were formed between different countries, leading to a complex web of obligations. Imperialism involved the competition for colonies and territories. Lastly, nationalism fueled a sense of patriotism and loyalty to one's own country.